#106

An important point there. Most of the sorts of timbres I work with aren’t ideally suited to polyphony, much less pianistic playing. If I were playing chords, or runs of notes that overlap, I would be much less interested in slightly-offtuned ratios and thick textures, and would probably appreciate those extra operators to bring in more transients.

I started out noodling on keyboards because that’s what was there – the family’s beat-up old upright piano, the little Magnus chord organ my grandma got me, the good ol’ Casio VL-1.

Back in 1988-89 I played keyboards (badly) in my (bad) high school jazz band and had some crash Suzuki Piano lessons in an attempt to suck a little bit less. I can jam a little bit but I’m definitely not a piano player in mindset. I’m probably at the least keyboard-player-ish point now that I’ve been since I was 8 years old or so :slight_smile:

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#107

OMG i dont even remember! Most likely something clever like 4OP_Matric_FM. I never published it. It was before there was an easy way to make PD patches widely available.

#108

I would like to ask a really basic analog FM question. What is the difference between a given module’s V/Oct pitch CV in and an FM in? I assume there’s a scaling difference. But, if I run a signal into a ‘pitch’ input, isn’t that modulating frequency?

Not concerned about the practicality of this or trying to get a steady recognizable pitch or bell tone or such, just understanding what kind of effect is happening. Thanks for any insight!

#109

A 1v/o input on a module is an exponential FM input. There is no difference to other exponential FM inputs, apart from a potentially present attenuator knob or internal vca to set the fm depth (you wouldn’t want that on the 1v/o input for obvious reasons).

There is a difference to linear FM inputs, but you probably know that.

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#110

There is basically no difference, although an FM input is more likely to have an attenuator, so you can add more or less modulation. A v/Oct input has no attenuator because it is precisely calibrated.
V/Oct VCOs all have an ‘exponential converter’ which turns the linear voltage (0 to 1v is the same as 3 to 4v) into a signal that can control a frequency that is exponential (1 extra volt doubles the frequency, 2 extra volts quadruples it, 3v = 8x frequency). The ‘linear fm’ input bypasses this exponential converter.

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#111

when i teach my students about FM synthesis (i usually use Ableton Live Operator for this) one of the aspects i insist mostly on is the expression, how expressive a simple fm patch can be if you start to add velocity to operators, and aftertouch. often they remain highly surprised by how a digital form of synthesis like dx style phase mod can be dramatically more expressive than an analog synth…

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#112

well, if fixed-architecture analog synths commonly had SIX envelope generators to control various parameters, maybe it’d be a fair fight :stuck_out_tongue_winking_eye:

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#113

i think this may be my favorite “how to” and to show new people. Helped me an absolute tonne

https://www.youtube.com/watch?v=ziFv00PegJg&t=0s&list=WL&index=73

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#114

Found this thread since I published a FM7 engine for Norns and have been in the FM spiral for a few weeks… it’s goes deeper than I expected.

Ironically, I don’t actually know much of the DX7 history and I’m learning as I go. The engine is in the master branch of dust.

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#115

The master branch of dust has an FM synth that uses a different UGen. I’ll be adding envelopes next week.

@zebra would you happen to know the differences between the FM7 UGen and this DX7Clone?

#116

@cannc 's DX7Clone.scd is a script that uses the FM7 ugen, with some supporting data files. it consists of synthdefs and a bunch of data parsing stuff, that help recreate DX7 presets.

i did a minor refactor to change it to a class, but didn’t do a bunch of necessary stuff - like taking that data out of a file and putting it into a separate static class variable (or something - in the original, the data file is read and parsed for every note event!) see my comments on my fork

#117

Cool. I’m not super worried about that then. I’m fine with providing the framework on Norns for someone else to make a sample accurate DX-7 clone :slight_smile: It’s a great reference point though!

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#118

well, it might be worth at least looking at the DX7Clone synthdefs, since there is a bunch of stuff that is necessary for actually making a DX7 clone, and not yet provided by your engine. (like pitch envelopes.)

or of course just leave it as “exercise to reader” :slight_smile:

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#119

This might be the wrong place to ask, but seems as good as any.

I’ve got a Digitone on the way and I’m somewhat confused by some of the literature. It says there are “four synths and four midi tracks”. Does that mean I can use midi to sequence four additional synths along with the four different onboard sounds, or do the midi tracks sequence the Digitone or external gear?

Not a deal breaker either way, I have other sequencers to use, but boy howdy that would be a cherry on top!

Also wtf I have an addiction to four-op FM between my FB-01, DX21, and now Digitone!

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#120

the midi sequence tracks are for sequencing external midi gear

however there is a trick you can do too - plug a midi cable from midi out into midi in and then you can use the sequencer tracks to provide additional modulation on the internal sequence tracks :slight_smile:

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#121

That’s awesome! I believe it can send CC changes right? I was watching a video where a guy would use his Digitakt to change presets on his Peak. I’ll be using an Electribe 2, Digitone, and Roland Gaia for live sets. I am assuming that Digitone CCs will be more customizable than what the E2 can do.

Edit: I know, I know rtfm :wink:

#122

Shout out to the Dexed plugin once again for being actually surprisingly painless to set up as an editor for my DX7! I configured 9*6=54(!) parameters to be controlled by my MIDI controller to make editing operator settings easier and even backed up all my patches to my computer already.

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#123

My uncle (very kindly) recently gave me his DX-21. It has just been gathering dust in his attic since he bought it in the 80’s (he’s a big Eno fan).

After all the stories I read about the DX synths being nightmares to program… I’m actually finding it quite nice to work with (much easier than my Korg Volca FM).

Does anyone have any good programming tips for getting patches at the softer and more melodic end of the scale (for ‘ambient’ music use).

Have any of you found particular algorithms or programming methods that lend themselves to choral/pad type patches?

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#124

From my experiments with the Digitone, I find that the more “soothing” timbres arise more often with cleaner ratios - so whole numbers and the 0.5’s in between. For low ratios you can sometimes squeeze a quarter (0.25) in as well. Other ratios tend to be harsher or introduce more complex overtone structures that are less harmonic.

I also use envelopes quite a lot - the initial “strike” may be fairly simple, and complexifies using envelopes on the operators. If you need a visual guide to what’s going on, the Arturia DX7 V has some very nice visuals that go along with the envelopes internally.

You can also set up some quite complex algorithms but shut some operators off by using a 1:1 ratio or 0 amount for them that is then linked in some way to a modulation control, letting you bring in whatever complexity they provide gently - like with a mod wheel or control pedal or aftertouch.

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#125

The more parallel / “additive” algorithms on the DX synths can be nice. On the DX100/21 it’d be algos 5-8 (especially 6 and 8).

Otherwise yeah, harmonic ratios – or perhaps really high ones with low FM indices – are key.

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